THE puzzle over what causes earthquakes deep beneath the Earth’s surface has ended – and loss of water seems to be to blame.
High pressures and temperatures at depth prevent the brittle failures causing most quakes. At less extreme depths, quakes can also be caused when the water is squeezed out of hydrated minerals, increasing the total volume and ramping up the pressure so that the rock cracks. Below this depth, the higher pressures compress the water so much that when it is squeezed out the total volume of the rock drops. Under these conditions, the rock should flow without breaking.…
